N-phosphorylamino acids can react to form esters, peptides, phosphoryl ester-exchanged products and phosphoryl group migration products under mild conditions which are very important in researches on the origin of life. It has been proposed that the penta-coordinate phosphorous compounds might be the common intermediates of these reactions, which are the key factor to determine the activities. In this paper, the mechanisms of series reactions involving N-phosphorylaminoacids and penta-coordinate phosphorous compounds are studied with computational chemistry methods